Walter Shapiro
... The sweeping decision by the Court's five-member conservative majority was immediately hailed by Republicans (aside from John McCain, who coauthored the 2002 law that was partially overturned) as an uplifting triumph for the First Amendment. In reality (and I know this will upset those who still believe in the Tooth Fairy), the GOP statements are mostly motivated by self-interest on the assumption that corporations will mostly want to back anti-tax and anti-government-regulation Republicans. Democratic dismay (Barack Obama warned of "a new stampede of special-interest money in our politics") also has its dollars-and-cents component as Obama raised five times more than McCain in 2008 from small (under $200) donors.
Thursday's ruling in Citizens United v. Federal Election Commission may prove to be the most significant political event (sorry about that Sen. Brown) since the 2008 election. Its potential implications are so vast that it is misleading to merely view the Citizens United case through a narrow partisan prism. Michael Waldman, a former Bill Clinton speechwriter who is now the executive director of the Brennan Center, a non-partisan public policy institute which specializes in political reform, said, "Exxon Mobil's profits in 2008 were $45 billion. At 9:00 Thursday morning, Exxon's manager could not spend any of that money to back candidates. And at noon Thursday, after the Supreme Court ruled, they could. There is nothing to prevent them from spending Mike Bloomberg-level money in every congressional district in the country" ...
http://www.politicsdaily.com/2010/01/22/the-supreme-court-s-ruling-on-corporate-campaign-spending-it-s/